WO2001056004A1 - Procedes et appareil d'attaque d'un affichage - Google Patents

Procedes et appareil d'attaque d'un affichage Download PDF

Info

Publication number
WO2001056004A1
WO2001056004A1 PCT/US2001/003113 US0103113W WO0156004A1 WO 2001056004 A1 WO2001056004 A1 WO 2001056004A1 US 0103113 W US0103113 W US 0103113W WO 0156004 A1 WO0156004 A1 WO 0156004A1
Authority
WO
WIPO (PCT)
Prior art keywords
phase
evolution
voltage
signal
preparation
Prior art date
Application number
PCT/US2001/003113
Other languages
English (en)
Inventor
Matthias Pfeiffer
Russell Flack
Anna Prakash
Original Assignee
Three-Five Systems, Inc.
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from PCT/US2000/025583 external-priority patent/WO2001020592A1/fr
Application filed by Three-Five Systems, Inc. filed Critical Three-Five Systems, Inc.
Priority to EP01903446A priority Critical patent/EP1166258A1/fr
Priority to AU2001231255A priority patent/AU2001231255A1/en
Publication of WO2001056004A1 publication Critical patent/WO2001056004A1/fr

Links

Classifications

    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G3/00—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
    • G09G3/20—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
    • G09G3/34—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters by control of light from an independent source
    • G09G3/36—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters by control of light from an independent source using liquid crystals
    • G09G3/3611—Control of matrices with row and column drivers
    • G09G3/3622—Control of matrices with row and column drivers using a passive matrix
    • G09G3/3629—Control of matrices with row and column drivers using a passive matrix using liquid crystals having memory effects, e.g. ferroelectric liquid crystals
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G2300/00—Aspects of the constitution of display devices
    • G09G2300/04—Structural and physical details of display devices
    • G09G2300/0469—Details of the physics of pixel operation
    • G09G2300/0478—Details of the physics of pixel operation related to liquid crystal pixels
    • G09G2300/0482—Use of memory effects in nematic liquid crystals
    • G09G2300/0486—Cholesteric liquid crystals, including chiral-nematic liquid crystals, with transitions between focal conic, planar, and homeotropic states
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G2310/00—Command of the display device
    • G09G2310/06—Details of flat display driving waveforms
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G2320/00—Control of display operating conditions
    • G09G2320/04—Maintaining the quality of display appearance
    • G09G2320/041—Temperature compensation
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G3/00—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
    • G09G3/04—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of a single character by selection from a plurality of characters, or by composing the character by combination of individual elements, e.g. segments using a combination of such display devices for composing words, rows or the like, in a frame with fixed character positions
    • G09G3/16—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of a single character by selection from a plurality of characters, or by composing the character by combination of individual elements, e.g. segments using a combination of such display devices for composing words, rows or the like, in a frame with fixed character positions by control of light from an independent source
    • G09G3/18—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of a single character by selection from a plurality of characters, or by composing the character by combination of individual elements, e.g. segments using a combination of such display devices for composing words, rows or the like, in a frame with fixed character positions by control of light from an independent source using liquid crystals

Definitions

  • the present invention generally relates to display (LCD) systems, and more particularly, to drive schemes for display systems.
  • Displays are commonly used to convey information in a variety of fields.
  • Computers, signs, telephones, televisions, kitchen appliances, vehicle cockpits and innumerable other devices use electronic displays.
  • Various applications require different kinds of displays, and display technology continuously advances to satisfy needs and improve performance of displays in old and new applications alike.
  • bistable displays such as cholesteric displays
  • bistable pixels operate in many environments and applications.
  • Bistable pixels typically exhibit at least two stable states, one generally reflective and the other generally transmissive, such that the pixel tends to retain the selected state after the voltage across the pixel is removed.
  • pixels may have only two states, whereas other displays provide shades of black, white, gray, colors, and the like, depending on the needs of the display system, using areas of dark or b ⁇ ght domains within the pixel
  • a drive circuit typically generates the voltages across the pixels to change the display
  • the drive circuit applies signals to a series of row and column electrodes that define a matrix of pixels
  • the signals are provided according to a selected drive scheme to determine how the signals are applied to the various electrodes to achieve the desired image on the display
  • a standard drive scheme is illustrated in Catchpole et al , U S Patent No 5,644,330, issued July 1, 1997
  • a cumulative drive scheme is illustrated in Huang
  • a dynamic drive scheme for cholesteric LCDs is illustrated in Huang et al , U S Patent No 5,748,277, issued May 5, 1998
  • a progressive scanning drive scheme starts signals with a delay for each row electrode with respect to the previous row electrode
  • each pixel in a single row is selected or deselected by a segment signal applied to the corresponding column electrode
  • the segment signal may create a pixel level that is either "select" or "non-select", that
  • a drive circuit configured to implement a conventional drive scheme may provide a common signal having four different phases (preparation, selection, evolution, and final) and a segment signal that selects the state of the relevant pixel
  • Each phase of the common signal normally includes two or more voltage levels
  • the segment signal normally requires at least two voltage levels
  • the drive circuit may provide ten or more different voltage levels to the electrodes
  • the appropriate voltage levels to achieve desired pixel states might not remain uniform over time and conditions
  • the temperature of the liquid crystal material may affect its optical characteristics
  • the signal voltage levels may need to be adjusted as a function of temperature for improved display performance
  • Such adjustments are typically made by adjusting or tuning one or more of the voltage levels of the common signal, for example
  • Conventional systems might use one or more variable voltage supplies Such supplies, however, often add cost, complexity, and power consumption to the drive circuit
  • a display svstem includes methods and apparatus for driving a cholesteric display system using pulse width modulation (PWM) to control the RMS voltage applied across the pixels of the display
  • PWM pulse width modulation
  • PWM may affect the RMS voltage applied across the liquid crystal material to compensate for display variations such as optical effects due to temperature changes or to achieve other effects upon the liquid crystal
  • FIGURE 1 illustrates a liquid crystal display (LCD) system in accordance with an exemplary embodiment of the present invention
  • FIGURE 2 illustrates a drive scheme for a choleste ⁇ c display in accordance with an exemplary embodiment of the present invention
  • FIGURE 3 illustrates a drive scheme for a cholesteric display using 100% Pulse Width Modulation (PWM) in accordance with an exemplary embodiment of the present invention
  • FIGURE 4 illustrates a drive scheme for a cholesteric display using 80% PWM in accordance with an exemplary embodiment of the present invention
  • FIGURE 5 illustrates a drive scheme for a cholesteric display using 30% PWM in accordance with an exemplary embodiment of the present invention
  • FIGURE 6 illustrates a drive scheme for a cholesteric display using 0% PWM in accordance with an exemplary embodiment of the present invention
  • FIGURE 7 illustrates a drive scheme method for a cholesteric display in accordance with an exemplary embodiment of the present invention.
  • the present invention may be described in terms of functional block components and various processing steps. Such functional blocks may be realized by any number of hardware and/or software components configured to perform the specified functions.
  • the present invention may employ various integrated circuit components, e.g., memory elements, signal processing and generation elements, power supplies, and the like, which may carry out a variety of functions under the control of one or more circuits, processors, or other control devices.
  • various aspects of the present invention may be practiced in any number of display contexts and the various systems described are merely exemplary applications for various aspects of the invention.
  • a display system in accordance with various aspects of the present invention may employ any number of conventional techniques and components, such as liquid crystal material, power supplies, drive signal generation and control techniques, and the like.
  • the present invention may be embodied as a method, a display system, a device for driving a display, and/or a computer program product.
  • the methods and apparatus according to various aspects of the present invention may take the form of a computer program product on a computer-readable storage medium having computer-readable program code means embodied in the storage medium.
  • a liquid crystal display (LCD) system 601 in accordance with an exemplary embodiment of the present invention includes a bistable display panel 603 having a liquid crystal layer 605 between two surfaces, such as a substrate 607 and a cover 609.
  • the substrate 607 may include, but is not limited to, glass, plastic, ceramic, or other suitable material, and may be selected according to any suitable criteria, such as transparency, durability, thermal characteristics, and/or the like.
  • the cover 609 may be comprised of any suitable material for containing the liquid crystal material and facilitating viewing.
  • suitable materials for the cover include soda lime glass, borosilicate glass (e.g., Schott borofloat 33 or Corning 1737F glass), and/or the like.
  • a set of row electrodes 611 are coupled to one surface, such as cover layer 609, and a set of column electrodes 613 are coupled to the other surface, such as substrate layer 607, for forming a field across the liquid crystal material.
  • the electrodes suitably form a matrix of pixels to allow addressing and control of individual pixels and/or icons.
  • the electrodes may be formed of any suitable material, such as indium tin oxide (ITO). Further, the electrodes may be configured in any appropriate manner or disposed on any suitable surface.
  • each electrode may be coated with an aligning layer, such as a conventional aligning layer of polyimide.
  • the liquid crystal material comprises a bistable liquid crystal material, such as a surface or polymer stabilized cholesteric liquid crystal material.
  • a suitable bistable material may have two stable states (reflective planar state (bright) and focal conic state (dark)) and two non-stable/intermediate states (homeotropic state and transient planar state).
  • the display system suitably employs a bistable chiral nematic liquid crystal (e.g., cholesteric) or any appropriate liquid crystal material, such as twisted nematic, super twisted nematic, ferroelectric, or other suitable liquid crystal materials. Any criteria may be used to select the liquid crystal, such as to substantially optimize various properties of the display system.
  • the thickness of the liquid crystal layer is substantially optimized for selected display characteristics.
  • LCD system 601 also includes a drive system.
  • the drive system applies voltages to the electrodes in accordance with a drive scheme to change the state of the liquid crystal material.
  • a dynamic drive scheme includes applying common signals to one set of electrodes (e.g., row electrodes) and segment signals to the other set of electrodes (e.g., column electrodes). Common signals may be applied to one or more row electrodes at the same time. Segment signals are applied to the column electrodes to select the desired state of the pixel.
  • the voltage across a pixel is defined by the difference between the common signal (e.g., row electrodes) and the segment signal (e.g., column electrodes).
  • the pixel responds according to the root-mean-square (RMS) voltage difference across the liquid crystal.
  • RMS root-mean-square
  • Generating a voltage across a pixel may activate, change the appearance, or otherwise modify the pixel depending on the needs of the display system.
  • the pixel is either dark (e.g., black) or bright (e.g., white).
  • the drive system includes a source 615 coupled to row and column electrodes 611, 613 for providing a selected RMS voltage across one or more pixels of cholesteric display panel 603 via row electrodes 61 1 and/or column electrodes 613.
  • a controller 617 is coupled to cholesteric display panel 603 and source 615 for facilitating adjustment of the root-mean-square voltage across the one or more pixels, for example using pulse width modulation (PWM).
  • PWM pulse width modulation
  • the controller 617 and source 615 may be implemented as separate components or integrated into a single device.
  • a sensor 619 may be coupled between cholesteric display panel 603 and controller 617 in order to feedback desired parameters to controller 617.
  • sensor 619 may include a temperature sensor (e.g., thermistor, diode, and/or the like) for sensing the temperature of the liquid crystal material and translating the temperature into a voltage (e.g., an RMS voltage).
  • a temperature sensor e.g., thermistor, diode, and/or the like
  • the drive system may compensate for optical effects by adjusting the RMS voltage based on the measured temperature from sensor 619.
  • sensor 619 may communicate with controller 617 in order to choose the amount of PWM depending on the reading (e.g., temperature reading) of sensor 619.
  • a drive scheme 101 for a cholesteric display in accordance with an exemplary embodiment of the present invention suitably includes a first waveform for one set of electrodes and a second waveform for another set of electrodes
  • Drive scheme 101 may also be a standard drive scheme, a cumulative drive scheme, or any other suitable drive scheme
  • the drive scheme suitably comprises a unipolar implementation of a dynamic drive scheme as described in provisional patent application entitled "METHOD AND APPARATUS FOR DRIVING A
  • a common signal waveform 103 (e g , one or more common signals) drives a set of row electrodes of the display
  • a segment signal waveform 105 (e g , one or more segment signals) drives a set of column electrodes of the display
  • Common signal waveform 103 suitably includes one or more phases e g , preparation phase 107, selection phase 109, evolution phase 1 1 1, and/or final phase 1 13
  • a high voltage e g , about 20 to 50 Volts
  • voltage levels are applied to the electrodes to either maintain the pixels in the homeotropic state or bring the pixels to the transient planar state and maintain the pixels in this state
  • one voltage level may be high enough to maintain the pixels in the homeotropic state without allowing the pixels to go into another state
  • Another voltage level may be low enough to allow a transition into the transient planar state and maintain the pixels in the transient planar state without allowing the pixels to shift to the reflective planar state
  • Specific "high” and “low” voltages may be selected according to any appropriate criteria, such as the particular liquid crystal material being used
  • the selection phase determines the final state of the pixel based on the voltage levels applied to the electrodes In this manner, control of the pixel states is based on the RMS voltage levels applied during the selection phase As such, control
  • each of preparation phase 107, selection phase 109, evolution phase 1 11, and/or final phase 1 13 of the common signal represents a unit pulse having multiple time slots, such as four slots in the present embodiment, where each time slot has a duration of time t n .
  • Each unit pulse may have any desired number of time slots and voltage levels.
  • each unit pulse of preparation phase 107, selection phase 109, evolution phase 111, and/or final phase 113 may be repeated any number of times during each respective phase.
  • Segment signal waveform 105 suitably comprises one of two possible unit pulses, unit pulse 106 and unit pulse 108, to select or de-select the pixel.
  • Segment signal waveform 105 may include any number of unit pulses 106 and/or 108.
  • common signal waveform 103 to the row electrodes and either a select segment signal or a deselect segment signal to the column electrodes generates desired RMS voltages across the pixels and drives them to their desired states.
  • the resulting voltages across the pixels may be characterized as a select waveform 1 17 or a deselect waveform 1 15
  • Deselect waveform 1 15 represents the difference between the voltage levels of common signal waveform 103 (e g , the row electrodes) and segment signal waveform 105 (e g , the column electrodes) while a deselect segment waveform, comprising repeated unit pulses 108, is applied
  • Deselect waveform 1 15 also includes one or more phases, such as phases corresponding to the preparation phase 121, selection phase 123, evolution phase 125, and/or final phase 127 applied by the common signal waveform 103
  • select waveform 1 17 represents the difference between the voltage levels of common signal waveform 103 and the select segment signal waveform 105, suitably comprising multiple unit pulses 106, and similarly comprises multiple
  • an alternative dynamic drive scheme 201 for a cholesteric display uses fewer voltage levels in the common signal and employs pulse width modulation (PWM) to control the RMS voltage applied to the liquid crystal in at least one of the phases
  • PWM pulse width modulation
  • PWM pulse width modulation
  • Using PWM for at least one of the common signal or the segment signal aids in adjusting the RMS voltage of the various waveforms 203, 205, 215, and/or 217 to drive the cholesteric display
  • PWM may be used during at least one of prepaiation phase 207, selection phase 209, evolution phase 21 1, and/or final phase 213
  • PWM may be used while applying at least one of unit pulse 206 and/or unit pulse 208 Any level between the maximum and minimum voltage levels may be used, and any of the phases (e g , preparation phase, selection phase, evolution phase, and/or final phase) may be selected during the PWM
  • the drive scheme may also be implemented using any other drive scheme, e g , standard drive scheme ,
  • the evolution phase of the common signal may be modulated using PWM
  • the modulated evolution phase of the common signal suitably comprises only voltage levels used in other phases, such as the preparation phase and the final phase
  • FIGURES 3 through 6 illustrate four phases of a common signal waveform 203, unit pulses 206, 208 of a segment signal waveform 205, and the resulting select waveform 217 and deselect waveform 215 for a unipolar three-phase implementation of a dynamic drive scheme
  • FIGURE 3 illustrates the common signal waveform 203 and resulting select and deselect waveforms 217, 215 for an evolution phase in which 100% of the PWM cycle is set at a selected voltage, such as the maximum voltage of the preparation phase portion of the common signal waveform 203, to obtain the maximum RMS voltage
  • FIGURES 4 through 6 depict versions of the common signal evolution phase modulated between the maximum voltage of the common signal preparation phase and the maximum voltage of the common signal final phase
  • FIGURE 4 depicts an 80% PWM adjustment of the evolution phase
  • FIGUREs 3, 4, 5, and 6 are merely examples of waveforms that may be applied according to various aspects of the present invention Any number of combinations of voltage levels and pulse widths may be used to obtain a desired RMS voltage to drive the cholesteric display
  • PWM may be used during any phase
  • PWM may be used during any phase
  • any other combination of PWM and/or voltage levels may be used depending on the needs of the display system
  • any percentage of PWM may be selected and the RMS voltage level of any phase may be used
  • the drive system applies PWM adjustments to select a voltage level of evolution phase 21 1, 225, and/or 233 during a fraction or portion of time slot t culinary at the maximum voltage level of preparation phase 207, 221 , and/or 229
  • the voltage level of final phase 213, 227, and/or 235, respectively, is applied during the remainder of time slot t n
  • two of the voltage levels of each of evolution phase 21 1 , 225, and/or 233 may be set substantially equal to the maximum (e g , the preparation phase) and minimum (e g , the final phase) voltage levels of the unipolar dynamic drive scheme
  • the present invention may facilitate adjustment of the RMS voltage during one or more of the preparation phase, the selection phase, the evolution phase, and/or the final phase without additional voltage levels for one or more of the preparation phase, the selection phase, the evolution phase, and/or the final phase
  • various aspects of the present invention may be applied to compensate for display variations or achieve selected display results, such as to provide temperature compensation
  • the drive system may compensate for optical effects by adjusting the RMS voltage based on the measured temperature
  • a drive system and method according to various aspects of the present invention allows for compensation for temperature dependent parameters (e g , changing drive voltage requirements of the liquid crystal as a function of temperature) without changing one or more of the voltage levels of drive scheme 201
  • a method for providing a drive scheme for a cholesteric display in accordance with an exemplary embodiment of the present invention includes generating a waveform (e g , waveform 203, waveform 205, dynamic drive waveform 215 and/or dynamic drive waveform 217) for a cholesteric display (e g , LCD system 601 and/or cholesteric display panel 603) having one or more of a common signal and/or segment signal (step 701)
  • One or more of the common signal or the segment signal may include one or more of a preparation phase, a selection phase, an evolution phase, and/or a final phase
  • the method also includes using pulse width modulation for one or more common signals and/or segment signals (step 703) Accordingly, pulse width modulation may be used for one or more of the preparation phase, the selection phase, the evolution phase, and/or the final phase
  • the method further includes adjusting a root-mean-square voltage of the waveform (e g , waveform 203, waveform 205, dynamic drive waveform
  • the present invention provides methods and apparatus for driving a display using fewer voltage supplies (e g , voltage levels)
  • the RMS voltage across any pixel during any phase may be adjusted to compensate for variables such as temperature
  • the RMS voltage across any pixel during any phase may be adjusted to achieve a gray scale
  • PWM facilitates adjustment of the RMS voltage during any phase of the drive scheme without changing the voltage levels of the waveform used for the drive scheme
  • PWM adjusts the RMS voltages between a substantial maximum and a substantial minimum voltage level of the drive scheme, such as the voltage levels of the preparation phase and the final phase

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • Computer Hardware Design (AREA)
  • General Physics & Mathematics (AREA)
  • Theoretical Computer Science (AREA)
  • Liquid Crystal (AREA)
  • Control Of Indicators Other Than Cathode Ray Tubes (AREA)

Abstract

La présente invention concerne des procédés et un appareil d'attaque d'un système d'affichage cholestérique utilisant un arrangement d'attaque dynamique. L'arrangement d'attaque dynamique est utilisé pour attaquer les électrodes de l'affichage cholestérique afin de procurer des états de pixels voulus. Les états de pixels sont commandés par la tension appliquée dans les pixels. La présente invention utilise la modulation de largeur d'impulsion (PWM) pendant l'arrangement d'attaque dynamique afin de commander la tension appliquée aux pixels. La modulation PWM peut être utilisée pendant n'importe quelle phase (par exemple, la phase de préparation, la phase de sélection, la phase d'évolution et/ou la phase finale) de la forme d'onde d'attaque dynamique selon les besoins du système d'affichage cholestérique.
PCT/US2001/003113 2000-01-31 2001-01-31 Procedes et appareil d'attaque d'un affichage WO2001056004A1 (fr)

Priority Applications (2)

Application Number Priority Date Filing Date Title
EP01903446A EP1166258A1 (fr) 2000-01-31 2001-01-31 Procedes et appareil d'attaque d'un affichage
AU2001231255A AU2001231255A1 (en) 2000-01-31 2001-01-31 Methods and apparatus for driving a display

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
US17921000P 2000-01-31 2000-01-31
US60/179,210 2000-01-31
USPCT/US00/25583 2000-09-18
PCT/US2000/025583 WO2001020592A1 (fr) 1999-09-17 2000-09-18 Systeme d'attaque pour affichage cholesterique

Publications (1)

Publication Number Publication Date
WO2001056004A1 true WO2001056004A1 (fr) 2001-08-02

Family

ID=22655679

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US2001/003113 WO2001056004A1 (fr) 2000-01-31 2001-01-31 Procedes et appareil d'attaque d'un affichage

Country Status (4)

Country Link
US (1) US6717561B1 (fr)
EP (1) EP1166258A1 (fr)
AU (1) AU2001231255A1 (fr)
WO (1) WO2001056004A1 (fr)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2005122124A1 (fr) * 2004-06-14 2005-12-22 Magink Display Technologies Ltd. Mecanismes de commande permettant d'entrainer un materiau de cristaux liquides cholesteriques dans un etat focal conique
KR100592237B1 (ko) * 2001-12-27 2006-06-23 삼성에스디아이 주식회사 알.엠.에스(ｒ．ｍ．ｓ) 전압을 이용한 콜레스테릭 액정표시 패널의 구동 방법
CN100416346C (zh) * 2003-01-29 2008-09-03 奇景光电股份有限公司 显示器的驱动方法

Families Citing this family (22)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP4258128B2 (ja) * 2001-03-13 2009-04-30 コニカミノルタホールディングス株式会社 液晶表示素子の駆動方法及び液晶表示装置
US7116287B2 (en) * 2001-05-09 2006-10-03 Eastman Kodak Company Drive for cholesteric liquid crystal displays
US7307608B2 (en) * 2002-03-08 2007-12-11 Industrial Technology Research Institute Unipolar drive chip for cholesteric liquid crystal displays
US8421828B2 (en) * 2002-05-10 2013-04-16 Jasper Display Corp. Modulation scheme for driving digital display systems
TWI298864B (en) * 2003-04-18 2008-07-11 Himax Tech Inc Driving method fro cholesteric texture liquid crystal display
JP3818273B2 (ja) * 2003-05-23 2006-09-06 コニカミノルタホールディングス株式会社 液晶表示素子の駆動方法及び液晶表示装置
WO2006051273A1 (fr) * 2004-11-10 2006-05-18 Magink Display Tecnologies Ltd. Schema d'excitation pour un ecran a cristaux liquides cholesteriques
JP4633538B2 (ja) * 2005-05-23 2011-02-16 三菱電機株式会社 画像表示装置及び大型画像表示装置
GB0512829D0 (en) * 2005-06-23 2005-08-03 Magink Display Technologies Video drive scheme for a cholesteric liquid crystal display device
US8269801B2 (en) * 2008-09-24 2012-09-18 3M Innovative Properties Company Unipolar gray scale drive scheme for cholesteric liquid crystal displays
US8217930B2 (en) * 2009-08-27 2012-07-10 3M Innovative Properties Company Fast transitions of large area cholesteric displays
CN102749774B (zh) * 2012-06-21 2015-01-28 京东方科技集团股份有限公司 阵列基板、显示设备、电子设备、扫描方法以及扫描装置
US9406269B2 (en) 2013-03-15 2016-08-02 Jasper Display Corp. System and method for pulse width modulating a scrolling color display
JP5976936B2 (ja) * 2013-07-11 2016-08-24 シチズンホールディングス株式会社 液晶装置
US11030942B2 (en) 2017-10-13 2021-06-08 Jasper Display Corporation Backplane adaptable to drive emissive pixel arrays of differing pitches
US10951875B2 (en) 2018-07-03 2021-03-16 Raxium, Inc. Display processing circuitry
US11710445B2 (en) 2019-01-24 2023-07-25 Google Llc Backplane configurations and operations
US11637219B2 (en) 2019-04-12 2023-04-25 Google Llc Monolithic integration of different light emitting structures on a same substrate
US11238782B2 (en) 2019-06-28 2022-02-01 Jasper Display Corp. Backplane for an array of emissive elements
US11626062B2 (en) 2020-02-18 2023-04-11 Google Llc System and method for modulating an array of emissive elements
US11538431B2 (en) 2020-06-29 2022-12-27 Google Llc Larger backplane suitable for high speed applications
US11810509B2 (en) 2021-07-14 2023-11-07 Google Llc Backplane and method for pulse width modulation

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5835075A (en) * 1993-02-25 1998-11-10 Seiko Epson Corporation Method of driving a liquid crystal display device
US5933203A (en) * 1997-01-08 1999-08-03 Advanced Display Systems, Inc. Apparatus for and method of driving a cholesteric liquid crystal flat panel display

Family Cites Families (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH07152017A (ja) * 1993-11-30 1995-06-16 Sony Corp 液晶素子の駆動方法及びその液晶素子
US5889566A (en) * 1994-04-11 1999-03-30 Advanced Display Systems, Inc. Multistable cholesteric liquid crystal devices driven by width-dependent voltage pulse
US5644330A (en) 1994-08-11 1997-07-01 Kent Displays, Inc. Driving method for polymer stabilized and polymer free liquid crystal displays
US5748277A (en) * 1995-02-17 1998-05-05 Kent State University Dynamic drive method and apparatus for a bistable liquid crystal display
DE69738881D1 (de) * 1996-03-07 2008-09-18 Optrex Kk Doppelbrechende flüssigkristall-anzeigevorrichtung
US6268840B1 (en) * 1997-05-12 2001-07-31 Kent Displays Incorporated Unipolar waveform drive method and apparatus for a bistable liquid crystal display
US6133895A (en) * 1997-06-04 2000-10-17 Kent Displays Incorporated Cumulative drive scheme and method for a liquid crystal display
US6204835B1 (en) * 1998-05-12 2001-03-20 Kent State University Cumulative two phase drive scheme for bistable cholesteric reflective displays
US6278429B1 (en) * 1998-09-11 2001-08-21 Kent State University Bistable reflective cholesteric liquid crystal displays utilizing super twisted nematic driver chips

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5835075A (en) * 1993-02-25 1998-11-10 Seiko Epson Corporation Method of driving a liquid crystal display device
US5933203A (en) * 1997-01-08 1999-08-03 Advanced Display Systems, Inc. Apparatus for and method of driving a cholesteric liquid crystal flat panel display

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
HUANG X -Y ET AL: "LP-1: LATE-NEWS POSTER: GRAY SCALE OF BISTABLE REFLECTIVE CHOLESTERIC DISPLAYS", SID INTERNATIONAL SYMPOSIUM DIGEST OF TECHNICAL PAPERS,US,SANTA ANA, CA: SID, vol. 29, 17 May 1998 (1998-05-17), pages 810 - 813, XP000792570, ISSN: 0098-966X *

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR100592237B1 (ko) * 2001-12-27 2006-06-23 삼성에스디아이 주식회사 알.엠.에스(ｒ．ｍ．ｓ) 전압을 이용한 콜레스테릭 액정표시 패널의 구동 방법
CN100416346C (zh) * 2003-01-29 2008-09-03 奇景光电股份有限公司 显示器的驱动方法
WO2005122124A1 (fr) * 2004-06-14 2005-12-22 Magink Display Technologies Ltd. Mecanismes de commande permettant d'entrainer un materiau de cristaux liquides cholesteriques dans un etat focal conique

Also Published As

Publication number Publication date
US6717561B1 (en) 2004-04-06
EP1166258A1 (fr) 2002-01-02
AU2001231255A1 (en) 2001-08-07

Similar Documents

Publication Publication Date Title
US6717561B1 (en) Driving a liquid crystal display
US5519411A (en) Liquid crystal display apparatus
CN1318184A (zh) 双稳态液晶显示器的快速寻址
KR100843685B1 (ko) 액정표시장치의 구동방법 및 장치
US5471229A (en) Driving method for liquid crystal device
JPS60123825A (ja) 液晶表示素子
JPH11153778A (ja) 液晶セルおよびその駆動方法
JP2000284254A (ja) 液晶表示装置
US6894668B2 (en) General 2 voltage levels driving scheme for cholesterical liquid crystal displays
US20090153757A1 (en) Liquid crystal display element, method of driving the element, and electronic paper having the element
US5856815A (en) Method of driving surface-stabilized ferroelectric liquid crystal display element for increasing the number of gray scales
JPH0434130B2 (fr)
EP0607598B1 (fr) Méthode et dispositif pour un panneau d'affichage à cristaux liquides
US6885357B2 (en) Method for writing pixels in a cholesteric liquid crystal display
GB2178582A (en) Liquid crystal apparatus and driving method therefor
US7379059B2 (en) Display apparatus, display method, liquid crystal driver circuit and liquid crystal driving method
KR20100054861A (ko) 단순 매트릭스형의 표시 소자를 갖는 표시 장치 및 단순 매트릭스 드라이버
GB2217089A (en) Display device
JP2977356B2 (ja) アクティブマトリックス液晶表示装置の駆動方法
JP2637517B2 (ja) 液晶装置
US6924783B2 (en) Drive scheme for cholesteric liquid crystal displays
JPH07140444A (ja) 液晶表示装置およびその駆動方法
JPH0446409B2 (fr)
JP3768316B2 (ja) 相転移型液晶表示素子の駆動方法および相転移型液晶表示装置
JPH07168159A (ja) 表示装置

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): AE AG AL AM AT AU AZ BA BB BG BR BY BZ CA CH CN CR CU CZ DE DK DM DZ EE ES FI GB GD GE GH GM HR HU ID IL IN IS JP KE KG KP KR KZ LC LK LR LS LT LU LV MA MD MG MK MN MW MX MZ NO NZ PL PT RO RU SD SE SG SI SK SL TJ TM TR TT TZ UA UG UZ VN YU ZA ZW

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): GH GM KE LS MW MZ SD SL SZ TZ UG ZW AM AZ BY KG KZ MD RU TJ TM AT BE CH CY DE DK ES FI FR GB GR IE IT LU MC NL PT SE TR BF BJ CF CG CI CM GA GN GW ML MR NE SN TD TG

121 Ep: the epo has been informed by wipo that ep was designated in this application
WWE Wipo information: entry into national phase

Ref document number: 2001903446

Country of ref document: EP

WWP Wipo information: published in national office

Ref document number: 2001903446

Country of ref document: EP

REG Reference to national code

Ref country code: DE

Ref legal event code: 8642

NENP Non-entry into the national phase

Ref country code: JP

WWW Wipo information: withdrawn in national office

Ref document number: 2001903446

Country of ref document: EP